diff options
author | Tang Junhui <tang.junhui@zte.com.cn> | 2018-03-06 00:41:54 +0300 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-03-06 00:43:05 +0300 |
commit | cc40daf91bdddbba72a4a8cd0860640e06668309 (patch) | |
tree | d38ac1c11465b91a2d3fb1d07b19ff2e93642d47 /drivers | |
parent | 661e50bc853209e41a5c14a290ca4decc43cbfd1 (diff) | |
download | linux-cc40daf91bdddbba72a4a8cd0860640e06668309.tar.xz |
bcache: fix crashes in duplicate cache device register
Kernel crashed when register a duplicate cache device, the call trace is
bellow:
[ 417.643790] CPU: 1 PID: 16886 Comm: bcache-register Tainted: G
W OE 4.15.5-amd64-preempt-sysrq-20171018 #2
[ 417.643861] Hardware name: LENOVO 20ERCTO1WW/20ERCTO1WW, BIOS
N1DET41W (1.15 ) 12/31/2015
[ 417.643870] RIP: 0010:bdevname+0x13/0x1e
[ 417.643876] RSP: 0018:ffffa3aa9138fd38 EFLAGS: 00010282
[ 417.643884] RAX: 0000000000000000 RBX: ffff8c8f2f2f8000 RCX: ffffd6701f8
c7edf
[ 417.643890] RDX: ffffa3aa9138fd88 RSI: ffffa3aa9138fd88 RDI: 00000000000
00000
[ 417.643895] RBP: ffffa3aa9138fde0 R08: ffffa3aa9138fae8 R09: 00000000000
1850e
[ 417.643901] R10: ffff8c8eed34b271 R11: ffff8c8eed34b250 R12: 00000000000
00000
[ 417.643906] R13: ffffd6701f78f940 R14: ffff8c8f38f80000 R15: ffff8c8ea7d
90000
[ 417.643913] FS: 00007fde7e66f500(0000) GS:ffff8c8f61440000(0000) knlGS:
0000000000000000
[ 417.643919] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 417.643925] CR2: 0000000000000314 CR3: 00000007e6fa0001 CR4: 00000000003
606e0
[ 417.643931] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000
00000
[ 417.643938] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 00000000000
00400
[ 417.643946] Call Trace:
[ 417.643978] register_bcache+0x1117/0x1270 [bcache]
[ 417.643994] ? slab_pre_alloc_hook+0x15/0x3c
[ 417.644001] ? slab_post_alloc_hook.isra.44+0xa/0x1a
[ 417.644013] ? kernfs_fop_write+0xf6/0x138
[ 417.644020] kernfs_fop_write+0xf6/0x138
[ 417.644031] __vfs_write+0x31/0xcc
[ 417.644043] ? current_kernel_time64+0x10/0x36
[ 417.644115] ? __audit_syscall_entry+0xbf/0xe3
[ 417.644124] vfs_write+0xa5/0xe2
[ 417.644133] SyS_write+0x5c/0x9f
[ 417.644144] do_syscall_64+0x72/0x81
[ 417.644161] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
[ 417.644169] RIP: 0033:0x7fde7e1c1974
[ 417.644175] RSP: 002b:00007fff13009a38 EFLAGS: 00000246 ORIG_RAX: 0000000
000000001
[ 417.644183] RAX: ffffffffffffffda RBX: 0000000001658280 RCX: 00007fde7e1c
1974
[ 417.644188] RDX: 000000000000000a RSI: 0000000001658280 RDI: 000000000000
0001
[ 417.644193] RBP: 000000000000000a R08: 0000000000000003 R09: 000000000000
0077
[ 417.644198] R10: 000000000000089e R11: 0000000000000246 R12: 000000000000
0001
[ 417.644203] R13: 000000000000000a R14: 7fffffffffffffff R15: 000000000000
0000
[ 417.644213] Code: c7 c2 83 6f ee 98 be 20 00 00 00 48 89 df e8 6c 27 3b 0
0 48 89 d8 5b c3 0f 1f 44 00 00 48 8b 47 70 48 89 f2 48 8b bf 80 00 00 00 <8
b> b0 14 03 00 00 e9 73 ff ff ff 0f 1f 44 00 00 48 8b 47 40 39
[ 417.644302] RIP: bdevname+0x13/0x1e RSP: ffffa3aa9138fd38
[ 417.644306] CR2: 0000000000000314
When registering duplicate cache device in register_cache(), after failure
on calling register_cache_set(), bch_cache_release() will be called, then
bdev will be freed, so bdevname(bdev, name) caused kernel crash.
Since bch_cache_release() will free bdev, so in this patch we make sure
bdev being freed if register_cache() fail, and do not free bdev again in
register_bcache() when register_cache() fail.
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Michael Lyle <mlyle@lyle.org>
Reviewed-by: Michael Lyle <mlyle@lyle.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/md/bcache/super.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 4d1d8dfb2d2a..58d8998529de 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1204,7 +1204,7 @@ static void register_bdev(struct cache_sb *sb, struct page *sb_page, return; err: - pr_notice("error opening %s: %s", bdevname(bdev, name), err); + pr_notice("error %s: %s", bdevname(bdev, name), err); bcache_device_stop(&dc->disk); } @@ -1883,6 +1883,8 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, const char *err = NULL; /* must be set for any error case */ int ret = 0; + bdevname(bdev, name); + memcpy(&ca->sb, sb, sizeof(struct cache_sb)); ca->bdev = bdev; ca->bdev->bd_holder = ca; @@ -1891,11 +1893,12 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, bio_first_bvec_all(&ca->sb_bio)->bv_page = sb_page; get_page(sb_page); - if (blk_queue_discard(bdev_get_queue(ca->bdev))) + if (blk_queue_discard(bdev_get_queue(bdev))) ca->discard = CACHE_DISCARD(&ca->sb); ret = cache_alloc(ca); if (ret != 0) { + blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL); if (ret == -ENOMEM) err = "cache_alloc(): -ENOMEM"; else @@ -1918,14 +1921,14 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page, goto out; } - pr_info("registered cache device %s", bdevname(bdev, name)); + pr_info("registered cache device %s", name); out: kobject_put(&ca->kobj); err: if (err) - pr_notice("error opening %s: %s", bdevname(bdev, name), err); + pr_notice("error %s: %s", name, err); return ret; } @@ -2014,6 +2017,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, if (err) goto err_close; + err = "failed to register device"; if (SB_IS_BDEV(sb)) { struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL); if (!dc) @@ -2028,7 +2032,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, goto err_close; if (register_cache(sb, sb_page, bdev, ca) != 0) - goto err_close; + goto err; } out: if (sb_page) @@ -2041,7 +2045,7 @@ out: err_close: blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL); err: - pr_info("error opening %s: %s", path, err); + pr_info("error %s: %s", path, err); ret = -EINVAL; goto out; } |